Credit Suisse
The logo of Swiss bank Credit Suisse is seen in front of a branch office in Zurich on Nov.21, 2013. Reuters/Arnd Wiegmann

WASHINGTON/NEW YORK (Reuters) -- Swiss bank Credit Suisse (NYSE:CS) pleaded guilty Monday to a criminal charge for its role in helping Americans dodge taxes, U.S. Attorney General Eric Holder said, and will pay more than $2.5 billion as part of an agreement with U.S. authorities.

Separately, the New York Department of Financial Services said it had determined not to revoke the bank's license in the state.

Credit Suisse said it expects no impact on its licenses or any material impact on operational or business capabilities from the plea agreement.

U.S. prosecutors criminally charged Credit Suisse and two of its units, saying the bank helped clients deceive U.S. tax authorities by concealing assets in illegal, undeclared bank accounts, in a conspiracy that spanned decades.

Credit Suisse will pay financial penalties to the U.S. Department of Justice, the Internal Revenue Service, the Federal Reserve and the New York State Department of Financial Services to settle the charges. It had already paid $200 million to the Securities and Exchange Commission.

A U.S. banking official also told Reuters that Credit Suisse must fire certain individuals who were previously indicted but were still being paid by the bank.

"This case shows that no financial institution, no matter its size or global reach, is above the law," Attorney General Eric Holder said at a press conference.

Credit Suisse Chief Executive Brady Dougan said in a statement, "We deeply regret the past misconduct that led to this settlement."

He added, "We have seen no material impact on our business resulting from the heightened public attention on this issue in the past several weeks."

The Swiss bank, which has a large business managing wealthy clients' money, helped them withdraw money from their undeclared accounts by either providing hand-delivered cash to the United States or using Credit Suisse's correspondent bank accounts in the U.S., the Justice Department said.

Credit Suisse was the largest bank to plead guilty to a criminal charge in 20 years, Holder said, amid a push by U.S. politicians for tougher punishments for big banks after the 2007-2009 financial crisis.

Dougan, who has come under pressure from Swiss politicians to resign, and Chairman Urs Rohner would both stay in their jobs as part of the settlement, a person close to Credit Suisse said on Monday.

U.S. authorities have not often sought criminal convictions against a financial institution, fearing it could put a firm out of business, and result in lost jobs for people that had nothing to do with the crime, or jeopardize the financial system.

Ahead of the official announcement of the agreement, financial markets had been calm in the face of potentially stiff penalties against Credit Suisse. There had been no indications other banks have stopped doing business with the Swiss bank. It was still obtaining short-term funds in the repo and commercial paper markets, analysts said.

(Reporting by Aruna Viswanatha in Washington, Karen Freifeld in New York, and Oliver Hirt in Zurich; Additional reporting by Dan Wilchins and Richard Leong in New York and Douwe Miedema in Washington; Writing by Douwe Miedema; Editing by Karey Van Hall, Jeffrey Benkoe and Bernard Orr)